Specification modification estimation method and specification modification estimation system

ABSTRACT

It is possible to provide a specification modification estimation method and a specification modification estimation system which can build-in a specification modification in a development plan in advance when performing software development. The system includes: I/O unit ( 1 ) which inputs development information associated with specification modification and outputs a calculation result of a development scale obtained by the specification modification; a database ( 3 ) which accumulates a digitalized environment affect in the software development; and specification modification estimation calculation unit ( 2 ) which calculates a product amount of the entire development scale in the specification modification according to the aforementioned development information and the information accumulated in the database. Thus, as is described in [0036] and [0037], it is possible to estimate a final entire development scale which fluctuates according to the specification modification at a pre-stage of a software development or during the development.

TECHNICAL FIELD

The present invention relates to a specification modification estimationmethod and a specification modification estimation system capable ofestimating a modification amount of a product amount supposed to beobtained through a specification modification of an arbitrary process orall processes when developing a software product.

BACKGROUND ART

In the past, as means for developing a software product, the waterfallmodel, in which a development process is modeled and the progress of awork flows from the top process to the bottom process, was generallyused

The waterfall model is based on a premise that when an upper processsuch as determination of specification is settled, a lower process isinitiated. However, a production period of a target product or theproductivity of software such as workers involved or the like, in eachprocess, is planed based on manhours in each process.

A productivity estimation method will not be described in detail herein,but various productivity estimation methods have recently been suggestedto estimate the productivity more accurately and exactly.

According to a related art, when the productivity in softwaredevelopment is estimated based on the scale of a software product and anecessary time for the software development, the number of source codelines, function points, the amount of document of the software product,or the like are used as a gauge of the scale. For this instance, theamount of necessary time for the development is determined based on thetotal number of engineers involved, working hours of each engineer, orthe like. However, since this method measures the productivity applyingthe uniform same value to all the engineers without taking a differencein the level of ability among individual engineers into account, it isnot be said to be an accurate method of estimating the productivity.

In an actual software development, it is very frequent that work in alower process is initiated before settlement of the specification in ahigher process and there are a number of products that become uselessdue to frequent modifications of the specification. For such a reason,it is difficult to estimate the productivity accurately.

Thus, as in Patent Document 1, the applicant of the invention havesuggested a software development account-adjustment management systemcapable of increasing a reliability by estimating productivity asprecisely as possible, establishing the plan of software development,and performing feedback of a difference between a development status andan initial plan to data serving as a base of the plan, when thedifference between the development status and the initial plan occurs.

Patent Document 1: Japanese Patent Application No. 2004-213880

According to Patent Document 1, since not only predetermined informationbut also information obtained through actual development can be updated,it is possible to repeatedly perform production management of softwaredevelopment and achieve an increased accuracy of the development plan.

In appraising the software development, modifications of thespecification that occur during the development and works which are notincluded in a software product are taken into consideration, resultingin a further increase in accuracy of the development plan.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

However, although this system is advantageous in that the accuracy ofthe plan is high compared with the estimation of a related art, thesystem may not deal with the case in which many times of modificationsof the specification are incorporated.

That is, when a specification modification is performed in the softwaredevelopment, status such as the development scale and an increase ofcost have to be reestimated every time that the modification of thespecification is performed, which leads to an exponential increase inthe development scale.

Thus, performing the specification modification as less as possible canyield a reduction of development cost. In the method disclosed in PatentDocument 1, however, the development cost changes depending on acorrelation of the amount of an existing system that is a base, anadditional amount, and a deletion amount. Therefore, the accuracy of theestimation may degrade whenever the specification modification isperformed.

Principal objects to be obtained by the invention are as follows.

A first object of the invention is to provide a specificationmodification estimation method and a specification modificationestimation system capable of incorporating specification modificationsinto a development plan before the outset of software development.

A second object of the invention is to provide a specificationmodification estimation method and a specification modificationestimation system capable of reducing development cost by estimating aspecification modification before initiation of software development.

A third object of the invention is to provide a specificationmodification estimation method and a specification modificationestimation system capable of estimating a specification modificationexactly whenever the specification modification is repeated.

Other objects of the invention are apparent from the description of thespecification, drawings, and particularly claims.

Means for Solving the Problems

In order to solve the above-mentioned problems, the invention provides amethod including recognizing development information on a specificationmodification input from a terminal of a user, calculating an initialscale, a yield, a specification modification ratio, and an entiredevelopment scale based on the development information stored in adatabase, and outputting and displaying calculated values onto theterminal.

Also, in order to solve the above-mentioned problems, the inventionprovides a system including an I/O unit for allowing input ofdevelopment information on a specification modification and output of acalculated result of a development scale obtained through thespecification modification, a database for allowing a quantifiedenvironmental influence rate on software development to accumulatetherein, and a specification modification estimation calculation unitfor calculating an amount of products over the entire development scaleobtained through the specification modification based on the developmentinformation and information accumulated in the database.

Specifically, in order to solve the above-mentioned problems, the aboveobjects of the invention can be achieved by employing novel andadvantageous means according the following super ordinate andsubordinate concepts described below.

According to a first aspect of the invention, there is provided aspecification modification estimation method of calculating fluctuationof a development scale that is resulted from a specificationmodification input from a terminal of a user during software developmentbased on development information obtained by quantifying information onthe specification modification and the development information stored ina database, and estimating an entire development scale according to themodified specification. The specification modification estimation methodincludes a development information recognition step of recognizing thedevelopment information input from the user, an initial scaledevelopment step of calculating an original development scale as aninitial scale by adding a product amount baseline included in thedevelopment information to a quantified environmental influence rate onsoftware development requested to and received from the database, ayield calculation step of calculating a yield which is a ratio of aresult obtained through the specification modification, based on theinitial scale, the number of times of specification modifications, and aproduct amount established at the time of specification modification andincluded in the development information, a specification modificationratio calculation step of calculating a modification amount of theproduct amount, which is included in the development information isperformed, when the specification modification is performed, as aspecification modification ratio, an entire development scalecalculation step of calculating the entire development scale obtainedthrough the specification modification by multiplying the initial scaleby the yield and the sum of specification modification ratios, and anentire development scale output step of outputting and displaying theentire development scale on the terminal of the user.

A method according to a second aspect of the invention employs thespecification modification estimation method in which the entiredevelopment scale described in the method according to the first aspectof the invention is calculated by calculating a development scale V_(ij)by an expression of V_(ij)≈V₀ε_(j)×(1+Σ_(i=j˜i)α_(ij)) on the assumptionthat the yield is ε_(j) and the specification modification ratio isα_(ij) when the initial scale V₀ is subjected to the specificationmodification i times (where i is a natural number) and is calculated byan expression of V≈Σ_(j=l˜n){V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij))} on theassumption that the entire development scale is V when the specificationmodification is performed by n times in total.

A method according to a third aspect of the invention employs thespecification modification estimation method in which the initial scaledescribed in the method according to the first or second aspect of theinvention is calculated by an expression of V₀=V_(B)×(1+Σγ) based on theassumption that the product amount baseline is V_(B) and theenvironmental influence rate on the software development is γ, and theinitial scale is V₀.

A method according to a fourth aspect of the invention employs thespecification modification estimation method in which the yielddescribed in any one of the first, second, and third aspects of themethod of the invention is calculated by an expression ofε_(j)={V_(j)/V₀}×100 on the assumption that a product amount at time jis V_(j) when the specification modification is performed i times at thetime j with the yield ε_(j).

A method according to a fifth aspect of the invention employs thespecification modification estimation method in which when thespecification moderation ratio is α_(ij), the specification modificationratio described in any one of the first, second, third and forth aspectsof the method of the invention is calculated by an expression ofα_(ij)=−V_(1ij)+V_(2ij)+V_(3ij) based on a rejection target ratioV_(1ij) which is a comparative ratio of a product amount of objects tobe rejected to the initial scale V₀ included in the developmentinformation, a rejection net ratio V_(2ij) which is a comparative ratioof a rejection net amount to the initial scale V₀, and an addition ratioV_(3ij) which is a comparative ratio of an additional amount to initialscale V₀.

A method according to a sixth aspect of the invention employs thespecification modification estimation method in which a specificationmodification amount H when the yield Σε_(j) is set to 1.0 and thespecification modification is performed on all the development units ntimes described in any one of the first, second, third, forth and fifthaspects of the method of the invention is calculated by an expression ofH=Σ_(j=1˜n){V₀×ε_(j)×{(1+Σ_(i=j˜i)α_(ij))−Σ_(i=j˜i)α_(ij))}.

A method according to a seventh aspect of the invention employs thespecification modification estimation method in which the entiredevelopment scale V_(k) when a declination occurs in previous processesk times at an i-th specification modification described in any one ofthe first, second, third, forth, fifth and sixth aspects of the methodof the invention is calculated by an expression ofV_(k)=Σ_(j=1˜n)V_(nj)=Σ_(j=1˜n){V₀×ε_(j)×Σ_(i=j˜i)α_(ij)}.

A system according to a first aspect of the invention employs thespecification modification estimation system comprising: an I/O unitconfigured to calculate fluctuation of a development scale obtainedthrough a specification modification during software development and forallowing inputting, transmitting, and outputting of developmentinformation obtained by quantifying information on the specificationmodification when an entire development scale obtained through thespecification modification is estimated; a database for allowing aquantified environment influence rate to accumulate therein whenperforming the software development; and a specification modificationestimation calculation unit configured to calculate a product amount ofthe entire development scale obtained through the specificationmodification based on a value input from the I/O unit and a value storedin the database, wherein the specification modification estimationcalculation unit includes: an initial scale development unit configuredto calculate an original development scale as an initial scale by addinga product amount baseline included in the development information to aquantified environmental influence rate on software developmentrequested to and received from the database; a yield calculation unitconfigured to calculate a yield which is a ratio of a result obtainedwhen the specification modification is performed, based on the initialscale, the number of times of the specification modification, and aproduct amount included in the development information at thespecification modification; a specification modification ratiocalculation unit configured to calculate a modification amount of theproduct amount, which is included in the development information, whenperforming the software development, as a specification modificationratio; and an entire development scale calculation unit configured tocalculate the entire development scale obtained through thespecification modification by multiplying the initial scale by the yieldratio and a sum of the specification modification ratios.

A system according to a second aspect of the invention employs thespecification modification estimation system in which the entiredevelopment scale calculation unit described in the system according tothe first aspect of the invention calculates an entire development scaleV_(ij) using an expression of V_(ij)≈V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij)) on theassumption that the yield is ε_(j) and the specification modificationratio described in first aspects of the invention of system is performedby n times in total.

A system according to a third aspect of the invention employs thespecification modification estimation system in which the initial scalecalculation unit described in the system according to the first orsecond aspect of the invention calculates the initial scale using anexpression of V₀=V_(B)×(1+Σγ) based on the product amount baseline V_(B)and the environmental influence rate on the software development γ onthe assumption that the initial scale is V₀.

A system according to a fourth aspect of the invention employs thespecification modification estimation system in which the yieldcalculation unit described in any one of the first, second, and thirdaspects of the system of the invention calculates the yield using anexpression of ε_(j)={V_(j)/V₀}×100 on the assumption that a productamount at time j is V_(j) when the specification modification isperformed i times at the time j with the yield ε_(j).

A system according to a fifth aspect of the invention employs thespecification modification estimation system in which the specificationmodification ratio described in any one of the first, second, third andfourth aspects of the system of the invention calculates thespecification modification ratio using an expression ofα_(ij)=−V_(1ij)+V_(2ij)+V_(3ij), based on a rejection target ratioV_(1ij) which is a comparative ratio of a product amount of objects tobe rejected to the initial scale V₀ included in the developmentinformation, a rejection net ratio V_(2ij) which is a comparative ratioof a rejection net amount to the initial scale V₀, and an addition ratioV_(3ij) which is a comparative ratio of an additional amount to initialscale V₀.

A system according to a sixth aspect of the invention employs thespecification modification estimation system in which when the yieldΣε_(j) is set to 1.0, the yield calculation unit described in any one ofthe first, second, third, fourth and fifth aspects of the system of theinvention calculates a specification modification amount H when thespecification modification is performed on all the development units ntimes is calculated by an expression ofH=Σ_(j=1˜n){V₀×ε_(j)×{(1+Σ_(i=j˜i)α_(ij))−Σ_(i=j˜i)α_(ij))}.

A system according to a seventh aspect of the invention employs thespecification modification estimation system in which the entiredevelopment scale calculation unit described in any one of the first,second, third, fourth, fifth and sixth aspects of the system of theinvention calculates the entire development scale V_(k), when adeclination occurs in previous processes k times at an i-thspecification modification, using an expression ofV_(k)=Σ_(j=1˜n)V_(nj)=Σ_(j=1˜n){V₀×ε_(j)×Σ_(i=j˜i)α_(ij)}.

EFFECTS OF THE INVENTION

According to the aspects of the invention, it is possible to incorporatethe estimation of the specification modification into the developmentplan in the case in which the specification modification occurs in apre-state of the software development.

It is possible to estimate the entire development scale resulting fromthe specification modifications occurring during the softwaredevelopment. Moreover, even when the specification modification isrepeated plural times, and it is possible to obtain an advantage that itis not necessary to modify the original development plan.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating the functional configuration of aspecification modification estimation system related to an exemplarysystem according to the invention.

FIG. 2 is a diagram illustrating the functional configuration of aspecification modification estimation calculation unit 2 related to theexemplary system according to the invention.

FIG. 3 is a flowchart illustrating a sequence according to an embodimentof the invention.

BRIEF DESCRIPTION OF LETTERS AND NUMERALS

-   -   A: SPECIFICATION MODIFICATION ESTIMATION SYSTEM    -   1: I/O UNIT    -   2: SPECIFICATION MODIFICATION ESTIMATION CALCULATION UNIT    -   3: DATABASE    -   21: INITIAL SCALE CALCULATION UNIT    -   22: YIELD CALCULATION UNIT    -   23: SPECIFICATION MODIFICATION RATIO CALCULATION UNIT    -   24: DEVELOPMENT SCALE CALCULATION UNIT    -   25: SPECIFICATION MODIFICATION AMOUNT CALCULATION UNIT    -   26: SPECIFICATION MODIFICATION CORRECTION UNIT    -   V_(O): INITIAL DEVELOPMENT SCALE    -   V_(B): PRODUCT AMOUNT BASELINE    -   V_(ij): DEVELOPMENT SCALE    -   V: ENTIRE DEVELOPMENT SCALE    -   γ: PRODUCT AMOUNT ENVIRONMENT VARIABLE    -   ε_(J): YIELD    -   α_(ij): SPECIFICATION MODIFICATION RATIO    -   α1: REJECTION TARGET AMOUNT    -   α2: REJECTION NET AMOUNT    -   α3: ADDITIONAL AMOUNT    -   V_(1ij): REJECTION TARGET RATIO    -   V_(2ij): REJECTION NET RATIO    -   V_(3ij): ADDITION RATIO    -   s1: ESSENTIAL INFORMATION    -   s2: OPTIONAL INFORMATION    -   H: SPECIFICATION MODIFICATION AMOUNT

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a system according to an exemplary embodiment will bedescribed with reference to the accompanying drawings.

(Exemplary System)

FIG. 1 is a diagram illustrating the functional configuration of thespecification modification estimation system corresponding to theexemplary system.

As shown in the drawing, a specification modification estimation systemA corresponding to the exemplary system includes an I/O unit 1 forallowing inputting and outputting of required information when a user ofthe system estimates a specification modification, a specificationmodification estimation calculation unit 2 for calculating a numeralvalue of a change of a development scale (product amount) caused by thespecification modification based on the information received from aninput unit, and an environment database 3 in which information onenvironment of software development that is used in the specificationmodification estimation calculation unit 2 for the specificationestimation used is accumulated.

The I/O unit 1, the specification modification estimation calculationunit 2, and the environment database 3 may be incorporated in a terminalsuch as a personal computer. However, the I/O unit 1 and thespecification modification estimation calculation unit 2 or theenvironment database 3 may be mounted in different terminals and may beconnected so as to communicate with each other via an Internet line, adedicated line, or the like.

The I/O unit 1, which is a constituent element of the system accordingto the invention, has a function of transmitting estimation detailsinput by the user to the specification modification estimationcalculation unit 2, when performing calculation for specificationestimation. In addition, the I/O unit 1 includes a data input portion(not shown) and a display portion displaying a calculation resultcalculated by the specification modification estimation calculation unit2. The I/O unit 1 is realized by a terminal apparatus such as a personalcomputer or a PDA as long as it satisfies all the above conditions.

The specification modification estimation calculation unit 2 is afunctional unit that receives the information transmitted from the I/Ounit 1 and calculates an amount of products (a product amount) that maybe obtained through the specification modification, based on the data.The specification modification estimation calculation unit 2 is realizedby a system having a calculation function in each functional unit of thespecification modification estimation calculation unit 2 describedbelow.

The environment database 3 is a database in which, as data, definitionsof variables used in the specification modification estimationcalculation unit 2 is accumulated, and which is a functional unit whichtransmits a value to the specification modification estimationcalculation unit 2 under the request from the specification modificationestimation calculation unit 2.

Next, detailed functional units in the specification modificationestimation calculation unit 2 of the system according to the inventionwill be described in detail with reference to FIG. 2. Hereinafter, theoverview of each respective functional unit of the specificationmodification estimation calculation unit 2 will be descried. Since thespecification modification estimation calculation unit 2 performscalculation based on numerical values of various developmentenvironmental factors, the configuration of each respective unit of thespecification modification estimation calculation unit 2 will be firstdescribed, and then the concepts of each respective functional unit,variables to be used, and the functional details will be described indetail.

As shown in the drawing, the specification modification estimationcalculation unit 2 of the specification estimation system A includes aninitial scale calculation unit 21 for receiving the informationtransmitted from the I/O unit 1 and calculating an initial scale of thesoftware development based on the received data, a yield calculationunit 22 and specification modification ratio calculation unit 23 forcalculating a yield and a specification modification ratio, respectivelyof each software based on the value of the initial scale received fromthe initial scale calculation unit 21, development scale calculationunit 24 for calculating a development scale obtained through thespecification modification based on the values transmitted from theinitial scale calculation unit 21, the yield calculation unit 22, andthe specification modification ratio calculation unit 23, aspecification modification amount calculation unit 25 for calculating aproduct amount obtained through the specification modification based onthe value calculated by the development scale calculation unit 24, and aspecification modification correction unit 26 for calculating adevelopment scale obtained by adjusting and correcting a declination ofthe specification modification process for the value calculated by thedevelopment scale calculation unit 24.

Hereinafter, the functions of the respective calculation unit, thedefinitions of the variables to be used, expressions used by thecalculation unit will be described.

(Initial Scale Calculation Unit)

First, the initial scale calculation unit 21 will be described. Theinitial scale calculation unit 21 is a calculation unit that calculatesan initial scale V₀ which is a process product amount (developmentscale) when there is no specification modification. The initial scale V₀is calculated by Expression 1.

[Expression 1]

V ₀ =V _(B)×(1+Σγ)  (1)

In this expression, V_(B) denotes a product amount baseline. The productamount baseline refers to a standard development scale of generalsoftware development.

γ denotes a product amount environment variable, and an influence ratecan be set for each characteristic of 21 items, based on a developmentrequest for each characteristic.

The characteristics of the product amount environment variables γ areshown in Table 1, and the influence rates need to be set in advance byterms of percentage. Data for the set influence rates may be stored inthe database 3, as shown in FIG. 1, and the initial scale calculationunit 21 may read the set values of the data from the database 3 via acommunication line such as the Internet or the dedicated line.Alternatively, even though not shown here, an influence rate database orthe like may be stored in the initial scale calculation unit 21.

TABLE 1 Functionality Finality, Correctness, Connectivity, Conformity,Security Reliability Maturity, Problem Tolerance, Recovery UsabilityUnderstandability, Acquirement, Operability Efficiency ExecutionEfficiency, Resource Efficiency Conservation Interpretation,Modification Workability, Experiment Transplantation EnvironmentApplicability, Transplantation Workability, Scale Conformity,Substitution

(Yield Calculation Unit)

Next, the yield calculation unit 22 will be described. A yield ε_(j)denotes an index value representing timing of the specificationmodification. The yield calculation unit 22 calculates the yield ε_(j)using the ratio of the product amount V_(j) at the time of a phase ofdevelopment to the initial scale V₀ transmitted from the initial scalecalculation unit 21 and is expressed by Expression 2.

[Expression 2]

ε_(i)(%)={V _(i) /V ₀}×100  (2)

(Specification Modification Ratio Calculation Unit)

The specification modification ratio calculation unit 23 calculates aspecification modification ratio α_(ij) which is a ratio of thespecification modification, which is an addition request or a deletionrequest for requiring addition to or deletion from the initialdevelopment request, to the initial scale V₀. Here, i denotes the numberof times of specification modifications expressed in writing for eachspecification modification.

The specification modification ratio calculation unit 23 calculates arejection target ratio expressed by Expression 3 which is a comparativeratio between an amount α1 of rejection objects in rejection scheduleand the initial scale V₀, a rejection net ratio V_(2ij) expressed byExpression 4 which is a comparative ratio between a rejection net amountα2 that is the amount of rejected products among the finished productsand the initial scale V₀, and an addition ratio V_(3ij) expressed byExpression 5 which is a comparative ratio between an additional amountα3 that is an amount to be added to the product amount due to thespecification modification and the initial scale V₀. Additionally, thespecification modification ratio calculation unit 23 calculates aspecification modification ratio α_(ij) by adding and/or subtractingthese ratios as shown in Expression 6.

[Expression 3]

V _(1ij)={α₁ /V ₀}×100  (3)

[Expression 4]

V _(2ij)={α₂ /V ₀}×100  (4)

[Expression 5]

V _(3ij)={α₃ /V ₀}×100  (5)

[Expression 6]

α_(ij) =−V _(1ij) +V _(2ij) +V _(3ij)  (6)

(Development Scale Calculation Unit)

The development scale calculation unit 24 calculates a development scaleV_(ij) that is a result obtained through i times of the specificationmodifications on the development unit j as expressed by Expression 7,based on the values calculated by the initial scale calculation unit 21,the yield calculation unit 22, and the specification modification ratiocalculation unit 23.

[Expression 7]

V _(ij) ≈V ₀×ε_(i)×(1+Σ_(i=j˜i)α_(ij))  (7)

The development scale calculation unit 24 calculates the entiredevelopment scale V that is a result obtained through the specificationmodifications performed on all of the development units n times (where nis a natural number) using Expression 8.

$\begin{matrix}\left\lbrack {{Expression}\mspace{14mu} 8} \right\rbrack & \; \\\begin{matrix}{V = {\sum\limits_{j = {1 \sim n}}V_{ni}}} \\{= {\sum\limits_{j = {1 \sim n}}\left\{ {V_{O} \times ɛ_{i} \times \left( {1 + {\sum\limits_{j = {1 \sim i}}\alpha_{ij}}} \right)} \right\}}}\end{matrix} & (8)\end{matrix}$

The I/O unit 1 can be input with the yields ε_(j) in advance and cancalculate the entire development scale V, for example, as in Expression10, when the sum of the yields ε_(j) is set to 1.0 in advance, as inExpression 9.

[Expression 9]

Σ_(i=1˜n)ε_(i)=1.0  (9)

[Expression 10]

V=V ₀+Σ_(i=1˜n) {V ₀×ε_(j)×Σ_(i=i˜n)α_(ij)}  (10)

(Specification Modification Amount Calculation Unit)

The specification modification amount calculation unit 25 receives theentire development scale V calculated by the development scalecalculation unit 24 and calculates a specification modification amount Hwhich is an amount of a change of the product amount generated throughthe specification modifications. Expression 11 is a calculationexpression of the specification modification amount H calculated basedon the result obtained by Expression 10.

[Expression 11]

H=Σ _(i=1˜n) {V ₀×ε_(j)×Σ_(i=j˜n)α_(ij)}  (11)

(Specification Modification Correction Unit)

The specification modification correction unit 26 is a calculation unitwhich corrects the specification modification amount when there is adeclination with a number of higher processes corresponding to k timesat the time of an i-th specification modification. As expressed inExpression 12, the specification modification correction unit 26receives the entire development scale V calculated by the developmentscale calculation unit 24 and the rejection net ratio V_(2ij) calculatedby the specification modification ratio calculation unit 22, andcalculates the entire development scale V where the process declinationis corrected by subtracting the received values.

$\begin{matrix}\left\lbrack {{Expression}\mspace{14mu} 12} \right\rbrack & \; \\\begin{matrix}{V_{k} = {\sum\limits_{j = {1 \sim n}}V_{ni}}} \\{= {\sum\limits_{j = {1 \sim n}}\left\{ {{V_{O} \times ɛ_{j} \times \left( {1 + {\sum\limits_{j = {1 \sim i}}\alpha_{ij}}} \right)} - {\sum\limits_{j = {1 \sim {nk}}}V_{2{ij}}}} \right\}}}\end{matrix} & (12)\end{matrix}$

The detailed configurations of the respective calculation units of thespecification modification estimation calculation unit 2 have hithertobeen described.

Embodiment

Next, an embodiment of the invention in which the above-described systemis used will be described with reference to the diagram illustrating theconfiguration of the system in FIG. 2 and a flowchart in FIG. 3.

First, when a user inputs, as the development information which isquantified information on the specification modification, essentialinformation s1 including development units j, the number (i) of times ofspecification modifications, and a product amount production baselineV_(B) and optional information s2 that is optionally input and includesthe yield ε_(j), the rejection target amount α1, the rejection netamount α2, and the additional amount α3, using the input unit such as akeyboard (not shown) of the I/O unit 1, these values are transmittedfrom the I/O unit 1 to the initial scale calculation unit 21 of thespecification modification estimation calculation unit 2 (ST 101).

When the essential information s1 and the essential information s2 arereceived from the I/O unit 1, the initial scale calculation unit 21requests the database 3 to transmit the product amount environmentvariables γ (ST 201).

The database 3 transmits the product amount environment variables γstored in the database to the initial scale calculation unit 21 inresponse to the request from the initial scale calculation unit (ST301).

The initial scale calculation unit 21 calculates the initial scale V₀using Expression 1 based on the essential information s1 and the productamount environment variables γ received from the database 3, andtransmits the essential information s1 and the optional information s2transmitted from the I/O unit 1 and the initial scale V₀ to the yieldcalculation unit 22 and the specification modification ratio calculationunit 23 (ST 202).

When the yield ε_(j) of the optional information s2 is transmitted fromthe I/O unit 1 (ST 203), the initial scale calculation unit 21 directlytransmits the initial scale V₀, the essential information s1, and theoptional information s2 to the development scale calculation unit 24,and transmits the rejection target amount al, the rejection net amountα2, and the additional amount α3 included in the optional information s2received from the I/O unit 1, in addition to the initial scale V₀, tothe specification modification ratio calculation unit 23.

On the other hand, when the yield ε_(j) is not included in the optionalinformation S2 (ST 203), the initial scale calculation unit 21 transmitsthe development unit j included in the essential information s1 and theinitial scale V₀ to the yield calculation unit 22, and transmits theessential information s1 and the initial scale V₀ to the developmentscale calculation unit 24.

Next, the yield calculation unit 22 requests the database 3 to transmitthe product amount V_(j) at the time j using the development unit j (ST204). The requested database 3 transmits the product amount V_(j) at thetime j to the yield calculation unit 22 (ST 302).

When the product V_(j) is received, the yield calculation unit 22calculates the yield ε_(j) using Expression 2 and transmits thecalculated value to the development scale calculation unit 24 (ST 205).

Next, the specification modification ratio calculation unit 23calculates the rejection target ratio V_(1ij), the rejection net ratioV_(2ij), and the addition ratio V_(3ij) using Expressions 3 to 5 basedon the initial scale V₀, the rejection target amount al, the rejectionnet amount α2, and the additional amount α3 received from the initialscale calculation unit 21. The specification modification ratiocalculation unit 23 calculates the specification modification ratioα_(ij) using Expression 6 based on the rejection target ratio V_(1ij),the rejection net ratio V_(2ij), and the addition ratio V_(3ij) andtransmits the calculated values to the development scale calculationunit 24 (ST 206).

The development scale calculation unit 24 calculates the developmentscale V_(ij) which is a result obtained through i times of thespecification modifications on the development unit j based on theessential information s1, the initial scale V₀, the yield ε_(j), and thespecification modification ratio α_(ij) transmitted from the initialdevelopment calculation unit 21 and the yield calculation unit 22, andthe specification modification ratio calculation unit 23 usingexpression 7 (ST 207).

The development scale calculation unit 24 calculates the entiredevelopment scale V which is a result obtained by performing n times ofspecification modifications (where n is a natural number) with respectto all of the development units, based on the development scale V_(ij),using Expression 8, and delivers the resultant entire development scaleV to the specification modification amount calculation unit 25 (ST 208).

The specification modification amount calculation unit 25 calculates thespecification modification amount H using Expression 11, based on theentire development scale V received from the development scalecalculation unit 24 (ST 209).

Here, when the declination occurs in k processes (where k is a naturalnumber) at the i-th specification modification, the number k, which isthe number of processes in which process declination has occurred, isinput into the I/O unit 1; the number k (the number of times ofoccurrence of the process declination) and the rejection net ratioV_(2ij) in each process are delivered sequentially in the order from theinitial scale development scale calculation unit 21 to the developmentscale calculation unit 24; the development scale calculation unit 24transmits the entire development scale V and the number k relating tothe process declination to the specification modification correctionunit 26; and the specification modification correction unit 26calculates a corrected entire development scale V_(k) obtained bycorrecting the process declination using Expression 12 (ST 210).

In the above description, the entire development scale V obtainedthrough the specification modifications performed n times for all of thedevelopment units j is calculated but the invention is not limitedthereto. For example, when the specification modification is performed ntimes evenly in the process of arbitrary development units j, the I/Ounit 1 inputs and sets both the yield ε_(j) obtained through thespecification modification and the specification modification ratioα_(ij) to given values. For example, the yield ε_(j)=1/n and thespecification modification ratio α_(ij)=α are set, a specificationmodification amount Ha is calculated by Expression 13, using the setvalues set in Expression 12.

[Expression 13]

H _(a) =V ₀×α×(n+1)/2  (13)

After the above-described calculation process ends, the developmentscale calculation unit 24 transmits the development scale V_(ij) and theentire development scale V to the I/O unit 1, the specificationmodification amount calculation unit 25 transmits the specificationmodification amount H to the I/O unit 1, and the specificationmodification correction unit 26 transmits the entire development scaleV_(k) obtained by correcting the process declination to the I/O unit 1(ST 211).

The I/O unit 1 which has received the values from the respectivecalculation units of the calculation unit 2 displays the calculatedresults on a display apparatus such as a monitor included in the I/Ounit 1 so that the user can check the estimated product amount throughthe specification modification in the form of specific numeral values(ST 102).

Even though the embodiment of the invention has hitherto been describedaccording to an example of the specification modification estimationsystem, the invention is not necessarily limited to the above-describedmeans. The invention is modified appropriately within the scope of theabove-described advantages.

1. A specification modification estimation method of calculatingfluctuation of a development scale originating in a specificationmodification during software development based on developmentinformation that is obtained by quantifying information on thespecification modification and the development information stored in adatabase, and estimating an entire development scale in thespecification modification, the specification modification estimationmethod comprising: a development information recognition step ofrecognizing the development information input from the user; an initialscale development step of calculating an original development scale asan initial scale by multiplying a product amount baseline included inthe development information by a value obtained by adding 1 to a totalsum of quantified environmental influence rates of software developmentrequested to and received from the database; a yield calculation step ofcalculating a yield which is a ratio of the initial scale to a productamount at the time of a specification modification to the initial scale,which is included in the development information; a specificationmodification ratio calculation step of calculating a productmodification degree, which is included in the developing information,when the software development is performed, as a specificationmodification ratio which is a ratio of a specification modificationamount to the initial scale; an entire development scale calculationstep of calculating the entire development scale obtained through thespecification modification by multiplying the initial scale by the yieldratio and a value obtained by adding 1 to a total sum of thespecification modification; and an entire development scale output stepof outputting and displaying the entire development scale on theterminal of the user.
 2. The specification modification estimationmethod according to claim 1, wherein the development scale is calculatedby an expression of V_(ij)≈V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij)) on theassumption that the initial scale is V₀, the yield is ε_(j), and thespecification modification ratio is α_(ij) when the initial scale issubjected to the specification modification i times (where i is anatural number) and is calculated by an expression ofV≈Σ_(j=1˜n){V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij))} on the assumption that theentire development scale is V when the specification modification isperformed by n times in total.
 3. The specification modificationestimation method according to claim 1, wherein the initial scale iscalculated by an expression of V₀=V_(B)×(1+Σγ) on the assumption thatthe initial scale is V₀, the product amount baseline is V_(B), and theenvironmental influence rate of the software development is γ.
 4. Thespecification modification estimation method according to claim 1,wherein the yield is calculated by an expression of ε_(j)={V_(j)/V₀}×100on the assumption that the yield is ε_(j), the initial scale is V₀, anda product amount at an initial value of a development unit j (where j isa natural number) included in the development information is V_(j). 5.The specification modification estimation method according to claim 1,wherein the specification modification ratio is calculated by anexpression of α_(ij)=−V_(1ij)+V_(2ij)+V_(3ij) on the assumption that thespecification moderation ratio is the initial development scale is V₀, arejection target ratio that is a ratio of a product amount of objects tobe rejected to the initial scale V₀ and is included in the environmentinformation is V_(1ij), a rejection net ratio of a rejection net amountto the initial scale V₀ is V_(2ij), and an addition ratio of anadditional amount to the initial scale V₀ is V_(3ij).
 6. Thespecification modification estimation method according to claim 1,wherein the specification modification ratio is calculated by anexpression of H=Σ_(j=1˜n){V₀×ε_(j)×Σ_(i=j˜i)α_(ij)} on the assumptionthat the initial scale is V₀, the yield is ε_(j), the specificationmodification ratio is α_(ij), and a specification modification ratioobtained through the specification modification on all of thedevelopment units n times is H.
 7. The specification modificationestimation method according to claim 1, wherein the entire developmentscale is calculated by an expression ofV_(k)=Σ_(j=1˜n)V_(nj)=Σ_(j=1˜n){V₀×ε_(j)×{(1+Σ_(i=j˜i)α_(ij))−Σ_(j=1˜n-k)V_(2ij)}on the assumption that the initial scale is V₀, the yield is ε_(j), thespecification modification ratio is α_(ij), an addition ratio of anadditional amount to the initial scale V₀ is V_(3ij), and the entiredevelopment scale when a declination occurs in previous processes ktimes (where k is a natural number) at an i-th specificationmodification is V_(k).
 8. A specification modification estimation systemcomprising: an I/O unit configured to calculate fluctuation of adevelopment scale originating in a specification modification duringsoftware development and to input, transmit, and output developmentinformation obtained by quantifying information on the specificationmodification when an entire development scale obtained through thespecification modification is estimated; a database configured to allowa quantified environment influence rate to accumulate therein when thesoftware development is performed; and a specification modificationestimation calculation unit configured to calculate a product amount ofthe entire development scale obtained through the specificationmodification based on a value input from the I/O unit and a value storedin the database, wherein the specification modification estimationcalculation unit includes: an initial scale calculation unit configuredto numerically calculating an initial development scale as an initialscale by multiplying a product amount baseline included in thedevelopment information by a value obtained by adding 1 to a total sumof the digitalized environmental influence rates requested to andreceived from the database; a yield calculation unit configured tocalculate a yield which is a ratio of the initial scale to a productamount, which is included in the development information, at thespecification modification; a specification modification ratiocalculation unit configured to calculate a product modification degree,which is included in the developing information, when the softwaredevelopment is performed, as a specification modification ratio which isa ratio of a specification modification amount to the initial scale; andan entire development scale calculation unit configured to calculate theentire development scale obtained through the specification modificationby multiplying the initial scale by the yield ratio and a value obtainedby adding 1 to a total sum of the specification modification.
 9. Thespecification modification estimation system according to claim 8,wherein the entire development scale calculation unit calculates thedevelopment scale using an expression ofV_(ij)≈V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij)) on the assumption that the initialscale is V₀, the yield is ε_(j), and the specification modificationratio is α_(ij) when the initial scale is subjected to the specificationmodification i times (where i is a natural number) and using anexpression of V≈Σ_(j=1˜n){V₀×ε_(j)×(1+Σ_(i=j˜i)α_(ij))} on theassumption that the entire development scale is V when the specificationmodification is performed n times in total.
 10. The specificationmodification estimation system according to claim 8, wherein the initialscale calculation unit calculates the initial scale using an expressionof V₀=V_(B)×(1+Σγ) on the assumption that the initial scale is V₀, theproduct amount baseline is V_(B), and the environmental influence rateof the software development is γ.
 11. The specification modificationestimation system according to claim 8, wherein the yield calculationunit calculates the yield using an expression of ε_(j)={V_(j)/V₀}×100 onthe assumption that the yield is ε_(j), the initial scale is V₀, and aproduct amount at an initial value of a development unit j (where j is anatural number) included in the development information is V_(j). 12.The specification modification estimation system according to claim 8,wherein the specification modification ratio calculation unit calculatesthe specification modification ratio using an expression ofα_(ij)=−V_(1ij)+V_(2ij)+V_(3ij) on the assumption that the specificationmoderation ratio is α_(ij), the initial development scale is V₀, arejection target ratio that is a ratio of a product amount of objects tobe rejected to the initial scale V₀ included in the environmentinformation is V_(1ij), a rejection net ratio of a rejection net amountto the initial scale V₀ is V_(2ij), and an addition ratio of anadditional amount to the initial scale V₀ is V_(3ij).
 13. Thespecification modification estimation system according to claim 8,wherein the specification modification amount is calculated by anexpression of H=Σ_(j=1˜n){V₀×ε_(j)×Σ_(i=j˜i)α_(ij)} on the assumptionthat the initial scale is V₀, the yield is ε_(j), the specificationmodification ratio is α_(ij), and a specification modification ratioobtained through the specification modification on all of thedevelopment units n times is H.
 14. The specification modificationestimation system according to claim 8, wherein the entire developmentscale is calculated by an expression ofV_(k)=Σ_(j=1˜n)V_(nj)=Σ_(j=1˜n){V₀×ε_(j)×{(1+Σ_(i=j˜i)α_(ij))−Σ_(j=1˜n-k)V_(2ij)}on the assumption that the initial scale is V₀, the yield is ε_(j), thespecification modification ratio is α_(ij), an addition ratio of anadditional amount to the initial scale V₀ is V_(3ij), and the entiredevelopment scale when a declination occurs in previous processes ktimes (where k is a natural number) at an i-th specificationmodification is V_(k).